It was the type of building that presents an emerging design challenge around the gritty edges of cities all over the country: the big vacant retail space. Repp Design + Construction’s transformation of a Tucson, Ariz., eyesore into its own 5,400-square-foot office is an adaptive reuse that is tuned to its Sonoran Desert environs. An open studio, filled with natural, indirect light from new glazing and a skylight, requires no artificial light during the day and is cooled with cross ventilation, enhanced with ceiling fans, to minimize dependence on air-conditioning in the late spring and early fall. The studio flows into a private courtyard, fashioned into a desert garden, that welcomes visitors and is shaded by a 5.5-kilowatt photovoltaic array. A large steel-and-concrete screen wall blocks both the blazing western sun and the traffic noise from nearby 1st Avenue from entering the studio. “In our communities, there are so many buildings like this that … you wish someone would decide to spend a little bit of money and make some contribution to the city by elevating this really old and ugly building, and that’s what they did,” juror Trey Trahan said. “It’s not the singular iconic building that creates a city; it’s all of these, what we think of as secondary background buildings.”